1 ACCEPTED ARTICLE This manuscript has been accepted after peer review and appears as an accepted article online prior to editing, proofing, and formal publication of the final Version. The authors are responsible for the content of this accepted article. Synthesis of functionalyzed imidazo[1,2]pyridines  domino A 3 coupling/cycloisomerization approach Yulia Volkova 1 *, Vladimir Gevorgyan 2 * 1 N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences 47 Leninsky pr., 119991 Moscow, Russia; е)mail: yavolkova@gmail.com, 2 Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Room 4500, Chicago, Illinois 60607, United States; е)mail: vlad@uic.edu Submitted December 13, 2016 Accepted March 10, 2017 Recent developments in the synthesis of imidazo[1,2$a]pyridines via the transition$metal catalyzed three$component heterocyclization of aldehyde, 2$aminopyridines, and alkyne are discussed in this Highlight. Keywords: imidazo[1,2$a]pyridine, A 3 $coupling, propargylamine intermediate. Imidazo[1,2$a]pyridines have received significant attention in synthetic organic chemistry in the past decade due to their biological importance. These medically relevant compounds are abundant in natural products and exhibit a broad range of biological activities, including antiviral, antiprotozoal, anti$herpes, anti$apoptotic, sedative, anxiolytic, anticonvulsant, and muscle$relaxant. 1 The core structure of imidazo[1,2$a]pyridines is present in many drugs, such as zolpidem, alpidem, zolimidine, olprinone, GSK812397, saripidem, and necopidem (Fig. 1). 2,3 Besides, this heterocyclic core has attracted attention of the synthetic community due to the prevalence of the imidazopyridine scaffold in dyes, ligands for metal catalysts, and electronic materials. 4–6